Locks for egg carton covers

ABSTRACT

This disclosure relates to one-piece molded plastic egg cartons in which a cover is hingeably connected to a carton body, and sidewalls of the cover and carton body remote from the hinge means are provided with interlocking means for maintaining the cover in its closed position. The interlocking means are defined by posts which project above the terminal edge of the carton body and are interlockably received within recess or means or openings in the carton sidewall. The posts are preferably constructed from flexible and reboundable material to permit temporary deformation incident to the opening and closing of the carton.

United States Patent Inventor Harold W. Voorhis Upper Nyack, N.Y.

Appl. No. 857,331

Filed Sept. 12, 1969 Patented Oct. 5, 1971 Assignee Continental Can Company, Inc.

New York, N.Y.

LOCKS FOR EGG CARTON COVERS [56] References Cited UNITED STATES PATENTS 2,560,847 7/1951 Chaplin 229/25 3,217,963 I l/l965 Alsman 229/25 Primary ExaminerDonald F. Norton Attorney-Diner, Brown, Ramik 8L Holt ABSTRACT: This disclosure relates to one-piece molded plastic egg cartons in which a cover is hingeably connected to a carton body, and sidewalls of the cover and carton body remote from the hinge means are provided with interlocking means for maintaining the cover in its closed position. The interlocking means are defined by posts which project above the terminal edge of the carton body and are interlockably received within recess or means or openings in the carton sidewall. The posts are preferably constructed from flexible and reboundable material to permit temporary deformation incident to the opening and closing of the carton.

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sum 2 or 2 INVEN TD R HQRDLD w. IDURH\S ZBjZm. $14

ATTORNEYS LOCKS roa EGG CARTON covsas A primary object of this invention is to provide a carton including a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, a fold line connecting a sidewall of the cover to a sidewall of the body whereby the cover may be swung between open and closed positions relative to the body, and means for interlockingly securing the other of the body and cover sidewalls to each other in the closed position, the securing means being defined by post means projecting beyond a terminal edge of the other body sidewall, recess means in the other cover sidewall, and at least a portion of the post means being disposed within the recess means in the closed position.

A further object of this invention is to provide a novel carton of the type heretofore set forth wherein the post means portion includes a terminal edge spaced a predetermined maximum distance from the fold line as measured normal thereto, the recess means includes an edge spaced a predetermined maximum distance from the fold line as measured normal thereto, and the last-mentioned distance is less than the firstmentioned distance whereby the other cover sidewall and/or the post means portion is temporarily deformed during a closing operation and inherently rebounds into the recess means during a closing operation.

A further object of this invention is to provide a novel carton heretofore defined wherein the recess means are in the form of slots of varied configurations, and the post means portio'ns are correspondingly contoured to the shape of the slots.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claimed subject matter, and the several views illustrated in the accompanying drawings.

IN THE DRAWING FIG. 1 is a top plan view of a novel carton constructed in accordance with this invention, with a portion of its cover removed for clarity, and illustrates a plurality of recessed posts defining downwardly diverging side walls which interlockingly engage within like downwardly diverging slots of the carton cover.

FIG. 2 is a side elevational view of the carton of FIG. 1, again with a portion of the cover removed for clarity, and more particularly illustrates the manner in which the posts are received within the slots of the cover.

FIG. 3 is a cross-sectional view taken generally along line 3-3 of FIG. 2, and illustrates the interlocked relationship between the cover and one of the carton body posts.

FIG. 4 is an enlarged fragmentary sectional view of one of the four pairs of identical slots, and illustrates a generally identical triangular locking tab positioned therebetween.

FIG. 5 is a top perspective view of another novel carton constructed in accordance with this invention, and illustrates a pair of upwardly projecting partially cutaway posts of a carton body interlocka'bly received within downwardly diverge slots of a cover sidewall.

FIG. 6 is an enlarged top plan view of the carton of FIG. 5

with a portion of the cover removed for clarity, and illustrates the manner in which a portion of one of the two posts is cut away to form a wall interlockingly received within each of the slots.

FlG. 7 is a side elevational view of the carton of FIGS. 5 and 6, again with a portion of the cover removed for clarity, and more clearly illustrates the configuration of the upstanding posts which project beyond a terminal edge of the carton body.

FIG. 8 is a sectional view taken generally along line 8-8 of FIG. 7, and illustrates the manner in which a wall of one of the posts is received within its associated cover slot.

Referenceis now made to FIGS. 1 through 4 ofthe drawings which illustrate a carton 50 constructed from a single piece of molded polystyrene or similar polymeric or copolymeric material. The c'a'rton 50 consists of 12 article-receiving cells, but'the number may vary as desired.

The carton 50 includes a carton body 51 having a pair of side walls 52, 53, a pair of end walls54, 55', and a bottom wall generally designated by the reference numeral 56. The bottom wall 56 is formed by a plurality of individual compartment bottom walls 57 of a plurality of identical compartments 58 adapted to receiveeggs or similar frangible or nonfrangible ar-' ticles (not shown). The compartments 58 are separated from each other by an upstanding longitudinal partition 59v which runs the length of the carton body along its center line between the end walls 54, 55, and a plurality of upstanding transverse partitions 60 disposed between the longitudinal partition 59 and the adjacent sidewalls 52, 53. The carton body 51 includes an uppermost terminal edge 61 which extends along the uppermost edges of the end walls 54, 55 and the side wall 53. The terminal edge 61 terminates at opposite ends of a fold line 62 which extends substantially the entire length of the sidewall 52 and serves to hingeably connect the carton body 51 to a cover 63.

The carton cover 63 is defined by a pair of sidewalls 64, 65, the latter of which is joined to the carton body sidewall 52 by the fold line 62, a pair of end walls 66, 67 and a top wall 68 provided with a pair of longitudinally extending partitions 70, 71 which are in alignment with the longitudinal partition 59 of the carton body 51.

The carton body 51 and the cover 63 include cooperative means, generally designated by the reference numeral 72 for maintaining the carton in its closed position. The interlocking means each include a generally upstanding post 73 fonned as an integral extension of the sidewall 53 projecting beyond the terminal edge 61 thereof. Each of the posts 73 is partially cut out at 73 to define a pair of slopingwalls 75, 76 diverging downwardly away from each other toward the tenninal edge 61. Each of the walls 75, 76 includes faces 77, 78 directed toward each other and terminal edges 80, 81.

Each of the interlocking means 72 is further defined by pairs of associated slots 82, 83 (FIG. 4) formed in the sidewall 64 of the cover 63 and opening through a terminal edge 85 at an angle corresponding to the slope of the walls 75, 76. Between each of the slots 82, 83 is a triangular extension 79 having triangular terminal end portions 86, 87.

Assuming that the carton 50 is in its open position and that articles have been placed in the compartments thereof, the cover 63 is hinged downwardly about the fold line 62 in a known manner.

Reference is now made to FIG. 3 of the drawings which indicates a dimension D4 between the fold line 62 and an interior surface (unnumbered) of the side wall 64 of the cover 63. The dimension D4 is appreciably less than the dimension D3 which is likewise measured between the fold line 62 and the terminal edges 80, 81 of the posts 73.

Referring to FIG. 2, there is illustrated a dimension D1 as measured between the ends of the locking tab 72 which is greater than a distance D2 between the faces 77, 78 of each slot 74. Likewise, a dimension D1 between the end of the leftmost locking tab 79 and the right-hand edge of the second locking tab 79 from the left is greater than a corresponding distance D2 between the face 77 of the leftmost post 73 and the face 78 of the second post 73 from the left. Finally, the largest dimension D1 as measured from the left edge of the leftmost locking tab 79 to the right edge of the right-handmost locking tab 79 is greater than the distance D2 between the face 77 of the leftmost post 73 and the face 78 of the rightmost post 73.

As the cover '63 descends and approaches the uppermost portions of the edges 80,81 of the posts 73, the tips or triangular portions 86, 87 first contact the uppermost portions of the walls 75, 76 because of the lesser dimension D4 as compared to the dimension D3 whereupon the triangular portions 86-, 87 are cammed progressively outwardly away from the normal plane of the sidewall 64 until the slots 82, 83 are in general alignment with the walls 75, 76.at which time the inherent reboundable nature of the material from whichthe carton is constructed causes the tips 86, '87 to rebound between the walls 75, 76 to thereby interlock the cover 63 in its closed position relative to the carton body 51. To open the cover it is merely necessary to grasp the sidewall 64 and draw the same outward to draw the triangular portions 86, 87 beyond walls 75, 76 at which time the cover 63 can be hinged to its open position.

Reference is now made to FIGS. 5 through 8 of the drawings which illustrate another carton l0 likewise preferably constructed from a single piece of molded polystyrene or similar polymeric or copolymeric material, although the invention and the various embodiments is equally applicable to molded pulp cartons. The carton 10, as the carton 50, is illustrated for the purpose of describing the invention as an egg carton consisting of 12 egg or similar article-receiving cells, but it is likewise to be understood that cartons adaptable for use in packaging articles other than eggs may incorporate the present invention.

The carton 10 includes a carton body 11 having a pair of sidewalls 12, 13, a pair of end walls 14, 15, and a bottom wall generally designated by the reference numeral 16. The bottom wall 16 is fonned by a plurality of individual compartment bottom walls 17 of a plurality of identical compartments 18 adapted to receive eggs or similar frangible or nonfrangible articles (not shown). The compartments 18 are separated from each other by an upstanding longitudinal partition 19 which runs the length of the carton body along its centerline between the end walls l4, l5, and a plurality of upstanding transverse partitions 20 disposed between the longitudinal partition 18 and the adjacent sidewalls 12, 13. The carton body 11 includes an uppermost tenninal edge 21 which extends along the uppermost edges of the end walls 14, and the sidewall 21. The terminal edge 21 terminates at opposite ends of a fold line 22 which extends substantially the entire length of the sidewall 12 and serves to hingeably connect the carton body 11 to a cover 23.

The carton cover 23 is defined by a pair of sidewalls 24, 25, the latter of which is joined to the carton body sidewall 12 by the fold line 22, a pair of end walls 26, 27 and a top wall 28 provided with a pair of longitudinally extending partitions 30, 31 which are in alignment with the longitudinal partition 18 of the carton body 11, as is clearly evident from FIG. 6 of the drawings.

The carton body 11 and the cover 23 include cooperative means, generally designated by the reference numeral 32 for maintaining the carton in its closed position. The interlocking means each include a generally upstanding post 33 formed as an integral extension of the sidewall 13 projecting beyond the terminal edge 21 thereof. Each of the posts are partially cut away along one side, as indicated at 34 (FIG. 6) to define a wall 35 inclined at an angle other than normal to the terminal edge 21. Each wall 35 includes a face 36 directed away from its adjacent end wall 14 or 15, and a terminal edge 37.

Each of the interlocking means 32 is further defined by an associated slot 38 formed in the sidewall 24 of the cover 23 and opening through a terminal edge 40 of the sidewall 24 at an angle other than normal thereto. As best viewed in FIG. 5 of the drawings, the slots 38 are in diverging relationship when viewed opening through the terminal edge 40 of the sidewall 24 while the walls 35 are in converging relationship upwardly and away from the terminal edge 21 of the carton body 11.

Reference is now made to FIG. 7 of the drawings which indicates a dimension D1 between a triangular portion 41 of the sidewall 24 adjacent each of the slots 38 and a distance D2 between the faces 36, 36 of the posts 33. It should be noted that the distance D1 is greater than the distance D2.

Additionally, reference is further made to FIG. 8 in which a distance D3 between the fold line 22 and the edge 37 is greater than a distance D4 likewise measured from the fold line 22 to an innermost surface 43 of the sidewall 24 adjacent its terminal edge 40.

Assuming that the carton 10 is in its open position and that articles have been placed in the compartments thereof, the cover 23 is hinged downwardly about the fold line 22 at which time the terminal edge 40 at its innermost surface 43 follows D2. Thus, the triangular portions are cammed temporarily outwardly until the slots 38 are in general alignment with the walls 35, at which time the triangular portions 41 rebound inwardly under the inherent bias thereof to a position at which the triangular portions 41 underlie the walls 35, as is best shown in FIGS. 7 and 8. In this position, theunderlying triangular portions 41 maintain the cover 23 in its closed position relative to the carton body 1 1, and to open the same it is merely necessary to grasp the sidewall 24 medially of the triangular portions 41 and pull the same outwardly to draw the triangular portions 41 beyond the walls 35 at which time the cover 23 can be hinged in a direction opposite to that indicated by the double headed arrow in FIG. 8. That is, in the reversev direction the triangular portions 41 must be temporarily deformed to draw the inner surface 43 adjacent the edge 40 beyond the edge 37 to clear the same after which the triangular portions free the cover 23 for movement to its fully opened position and, again, the reboundable characteristics thereof return the triangular portions to the normal position in the plane of the sidewall 24.

While preferred forms and arrangements of parts have been shown in illustrating the invention, it is to be clearly understood that various changes in details and arrangement of parts may be made without departing from the spirit and scope of this disclosure.

I claim:

1. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means are defined by a plurality of slots formed in said other cover sidewall at an angle other than normal to a terminal edge thereof, and said post means portion is a post sidewall received in each slot.

2. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of saidcover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a tenninal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means are defined by a plurality of slots formed in said other cover sidewall at an angle other than normal to a terminal edge thereof, said post means portion is a post sidewall received in each slot, and each of said last-mentioned sidewalls is disposed at an angle corresponding generally to the angle of its associated slot.

3. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position and said recess means are slots arranged in at least a single pair diverging toward the tenninal edge of said other cover sidewall.

4. The carton as defined in claim 3 wherein said slots open outwardly through said terminal edge and in part set off a trapezoidal shaped portion of said other cover sidewall disposed between said post means.

5. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means are arranged in a plurality of pairs, each pair diverges toward the terminal edge of said other cover sidewall, and each post means portion is a pair of spaced post sidewalls received in each pair of recess means.

6. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means is a slot formed in said other cover sidewall opening through a terminal edge thereof, said post means portion is a post sidewall received in said slot, and said post sidewall and slot are of a generally identical configuration.

7. The carton as defined in claim 6 wherein said recess means includes an additional slot formed in said other cover sidewall opening through said last-mentioned terminal edge, said post means portion includes an additional post sidewall received in said additional slot, and said additional slot and ad- I ditional post sidewall are of a generally identical configura- 

1. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means are defined by a plurality of slots formed in said other cover sidewall at an angle other than normal to a terminal edge thereof, and said post means portion is a post sidewall received in each slot.
 2. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means are defined by a plurality of slots formed in said other cover sidewall at an angle other than normal to a terminal edge thereof, said post means portion is a post sidewall received in each slot, and each of said last-mentioned sidewalls is disposed at an angle corresponding generally to the angle of its associated slot.
 3. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position and said recess means are slots arranged in at least a single pair diverging toward the terminal edge of said other cover sidewall.
 4. The carton as defined in claim 3 wherein said slots open outwardly through said terminal edge and in part set off a trapezoidal shaped portion of said other cover sidewall disposed between said post means.
 5. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projecting beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means are arranged in a plurality of pairs, each pair diverges toward the terminal edge of said other cover sidewall, and each post means portion is a pair of spaced post sidewalls received in each pair of recess means.
 6. A carton comprising a body defined by a pair of end walls, a pair of sidewalls, and a bottom wall, a cover defined by a pair of end walls, a pair of sidewalls, and a top wall, means hingeably connecting a sidewall of said cover to a sidewall of said body whereby said cover may be swung between open and closed positions relative to said body, means for interlockingly securing the other of said body and cover sidewalls to each other in said closed position, said securing means being defined by post means projectiNg beyond a terminal edge of said other body sidewall, recess means in said other cover sidewall, at least a portion of said post means being disposed within said recess means in said closed position, said recess means is a slot formed in said other cover sidewall opening through a terminal edge thereof, said post means portion is a post sidewall received in said slot, and said post sidewall and slot are of a generally identical configuration.
 7. The carton as defined in claim 6 wherein said recess means includes an additional slot formed in said other cover sidewall opening through said last-mentioned terminal edge, said post means portion includes an additional post sidewall received in said additional slot, and said additional slot and additional post sidewall are of a generally identical configuration.
 8. The carton as defined in claim 7 wherein said slots diverge away from each other in a direction toward said last-mentioned terminal edge. 